Citation: Oyapero A, et al. Awareness and Oral Self-Care Practices of Diabetic Patients at a Tertiary Hospital in Lagos. Ann Med Health Sci Res. 2017; 7: 36-43

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Abstract

Background: Diabetes mellitus is a diverse group of metabolic disorders initiated by either a lack of insulin, resistance to its effects, or both. The oral cavity and its associated structures are also affected by the local and systemic effects of this condition. The aim of this study was thus to determine the oral health awareness and oral self-care practices of a group of patients registered for care at the diabetic clinic of the Lagos State University Teaching Hospital, Ikeja, Lagos State (Lasuth). Methods: This descriptive cross-sectional study was conducted at Lasuth. The study included 120 respondents. A structure interviewer administered questionnaire was used to assess the social background, medical history, utilization of dental services and the knowledge, values and attitude of the respondents towards oral health. Results: Pain or emergency treatment 64 (53.3%) was the main reason for dental attendance and the primary reason for not attending the dental clinic was perceived lack of need for dental care (22; 18.3%). Xerostomia or dry mouth (89; 74.2%) was the commonest dental complaints by the participants. There was a significant association between the age (p=0.000); educational qualification (p= 0.000); smoking status (p=0.000); duration of diabetes (p=0.000); diabetes type (p=0.000); blood sugar control (p=0.000); and the amount of oral health information received (p=0.000); with the number of dental complications experienced by the participants. Conclusion: This study revealed that the oral self-care behaviour of patients with diabetes was not consistent with their increased risk for oral diseases. Our findings suggest that there is a significant need for increased knowledge of the oral complications of diabetes mellitus and the adoption of preventive oral hygiene behaviours that would improve their oral health.

Keywords

Diabetes mellitus; Oral self-care; Oral health status; Dental services utilisation

Introduction

Diabetes mellitus is a diverse group of metabolic disorders initiated by either a lack of insulin, resistance to its effects, or both. [1] Patients with diabetes commonly experience hyperglycaemia as a result of the body’s inability to maintain normal blood glucose levels through normal homeostatic mechanisms. Currently, diabetes mellitus is categorized into four main classes: Type 1 diabetes (formerly known as insulindependent diabetes mellitus -IDDM); Type 2 diabetes (noninsulin- dependent diabetes mellitus -NIDDM); Gestational diabetes (a form of glucose intolerance diagnosed during pregnancy) and other types of diabetes caused by definite disorders such as surgery, medications, infections, pancreatic disease and other illnesses. [2] The major burden of morbidity and mortality of Diabetes mellitus falls on the developing world. [3] Diabetes negatively impacts physical (development of short- and long-term complications), psychological (altered mood, frustration and anxiety) [4] and social (alteration in the quantity and the quality of patients relationships) functioning. Diabetes mellitus also has unfavourable effects on quality of life outcomes [5] and studies have shown significant negative associations for health related quality of life. [6]

Body tissues in diabetic patients are subject to biochemical disorders which result in impairment and loss of function. Patients with diabetes mellitus have a range of systemic complications from microvascular and macrovascular disease as well as an increased susceptibility to infection and poor wound healing. The oral cavity and its associated structures are also affected by the local and systemic effects of this condition. Hyperglycaemia increases the development of advanced glycation end-products (AGEs) and the increased exposure of oral tissue proteins and lipids to aldose sugars, which induces non-enzymatic glycation and oxidation. [7] Degenerative vascular changes associated with diabetes also impede nutrient and leukocyte migration to gingival tissues, thus reducing oxygen diffusion and removal of metabolic waste products thus increasing the severity of oral diseases. [8]

Several soft tissue abnormalities have been associated with diabetes mellitus in the oral cavity. These complications include periodontal diseases, oral fungal and bacterial infections and salivary dysfunction. They also have reduced salivary flow rates, altered salivary components and a higher salivary glucose concentration. [9] Other oral mucosa lesions in diabetic patients are stomatitis, benign migratory glossitis, lichen planus, lichenoid reactions, fissured tongue, traumatic ulcer, and angular chelitis. [10,11] In addition, delayed mucosal wound healing, mucosal neuro-sensory disorders, dental caries and tooth loss have been reported in patients with diabetes. [12] The prevalence of oral mucosal lesions in patients with diabetes is higher compared to healthy controls. [13]

Dental plaque and plaque retentive factors such as calculus and overhanging margins of restorations are required for periodontal diseases to develop even in patients with diabetes mellitus. [14] Personal and professional plaque control measures [15,16] and oral self-care practices are critical factors in the prevention and treatment of periodontal diseases. Syrjälä et al. [17] observed that diabetic patients that had a better tooth brushing effectiveness with lower levels of plaque deposit had better glycated haemoglobin (HbA1c) levels. Regular dental visits are also an opportunity for professional help in the prevention, early detection, and treatment of oral conditions associated with diabetes mellitus. Similarly, adequate glycaemic control is also indispensable for the prevention of other oral complications associated with diabetes mellitus. However, in spite of the predisposition to oral complications among patients with diabetes mellitus, very few studies have explores the knowledge and oral self-care practices among patients with diabetes in Nigeria.

The aim of this study was thus to determine the oral health awareness and oral self-care practices of a group of patients registered for care at the diabetic clinic of the Lagos State University Teaching Hospital, Ikeja, Lagos State (LASUTH).

Material and Methods

Study design

This descriptive cross-sectional study was conducted at the Lagos State University Teaching Hospital, Ikeja, Lagos, Nigeria.

Study setting and location

This study was conducted at the Diabetic Clinic (Department of Medicine) of the Lagos State University Teaching Hospital, (LASUTH), Ikeja, Lagos, Nigeria. Lagos State University Teaching Hospital is a tertiary health facility situated in the capital of Lagos State. It is a multi-specialist hospital with a bed complement of 741. The diabetic Clinic in the Department of Medicine at LASUTH is a specialist facility with Consultant Endocrinologists that attend to over 50 diabetic patients on the clinic days on Tuesdays and Thursdays.

Sample selection

A simple random probability sampling method was utilised to enlist participants for the study with the attendance register for each clinic day serving as the sampling frame. Diabetic patients who were willing to give their informed consent were included in the study after checking them with set inclusion and exclusion criteria.

Sample size determination

The estimated sample size was computed using an equation for Cross-sectional studies. Using a prevalence of 10.8% for accessing dental care from a previous study [18] among diabetic patients, a sample size of 77 was calculated. One hundred and twenty questionnaires were however administered during the study period.

Inclusion/exclusion criteria

Subjects included in the study were 18 years or older and diagnosed as having had type 1 or 2 diabetes for at least one year before the study commenced. Patients that were excluded from the study included those who were those that had commenced dental/periodontal treatment recently and those that recently had a session of oral health education by a dental professional.

Ethical aspects

The study was questionnaire based and did not involve oral examination nor any form of dental intervention. All participants completed a written informed consent. The informed consent form contained the names and affiliation of investigators, a plain language description of the study.

Data collection

Questionnaires: Selected subjects completed an interviewer administered questionnaire designed to obtain information on the subjects’ bio-data and dental history. The questions were closed-ended and mostly multiple choice with alternative statements. They were grouped into five categories and the questions covered 1) social background, 2) medical history, 3) self-treatment, -prevention and -diagnosis of oral diseases, 4) utilization of dental services and 5) knowledge, values and attitude towards oral health.

Medical history/Behavioural factors: Diabetes was categorized as type 1 or 2 and HbA1c levels were classified as follows: < 7.5% as good glycaemic control, 7.5-8.5% as moderate control, 8.6-10.0% as poor control while behavioural factors included questions about smoking habit. Smoking habit was dichotomized as smoking and no smoking.

Oral self-care practices and awareness: Oral hygiene habits such as tooth brushing frequency, interdental cleaning, selfreported condition of oral health status and awareness of the oral complications was recorded.

Utilization of dental services: The frequency of utilization of dental services, the type of dental facility accessed and the type of dental condition that the participants had was also recorded in the questionnaire.

Knowledge, values and attitudes towards oral health: The questionnaire explored cognitive aspects about knowledge of the participants on the relationship between diabetes and periodontal diseases and affective domains on the importance of oral health which were answered in a Likert scale with responses such as fully agree, somewhat agree, I do not know, somewhat disagree, and fully disagree.

Data analysis

The data was analysed using SPSS (Statistical package for social sciences) for Windows (version 20, Chicago, IL) statistical software package. Frequency tables were generated for all variables and measures of central tendency and dispersion were computed for numerical variables. Since the data were normally distributed, descriptive statistics including means, standard deviations, and percentages were used to present the demographic variables and health-related behavior of the study sample. The Chi square test was used to determine the level of association between variables. The Student’s paired t tests and Anova tests were used to compare means. A 95% confidence interval and a 5% level of significance was adopted.

Results

A total of 120 patients were included in the study: 75 (62.5%) men and 45 (37.5%) women. The age range of patients was 38-72 years. When participants were subdivided into three age groups, those aged 46-65 years made up the majority 107 (89.2%). The sample consisted mainly of the Yoruba tribe 91 (75.8%) and majority had a secondary level of education 49(40.8%) [Table 1].

Table 1: Socio-demographic characteristics of responde

Only 3 (2.5%) of the participants were current smokers while 11 (9.2%) of them had a history of tobacco smoking. Majority of the participants 101 (85.8%) had Type 2 diabetes with most of them 47 (39.2%) were diagnosed 6-10 years previously. Most of the respondents 51 (42.5%) also rated their glycaemic control as fair and had a diabetes related complication 113 (94.2%). The commonest diabetic complication was numbness of the feet 77 (64.2%) [Table 2].

Table 2: Clinical Characteristics of the participants.

Only 18 (15.0%) of the respondents had a recent dental appointment within 1 year and the General Hospital was the preferred clinic for those that attended for a dental appointment 42 (46.7%). Pain or emergency treatment 64 (53.3%) was the main reason for dental attendance and the primary reason for not attending the dental clinic was perceived lack of need for dental care (22; 18.3%). Xerostomia or dry mouth (89; 74.2%); Bleeding gums (74; 61.7%) and a loose denture (65; 54.2%) were the commonest dental complaints by the participants and most of them (52; 43.3%) felt that their oral health status was average [Table 3].

Table 3: Oral health status and use of dental services by participants (multiple responses).

Most of the participants (71; 59.2%) had received insufficient information about oral care and the diabetes nurse (46; 43.0%) was the primary source of this information. Most of them (87; 72.5%) had never received a physician’s referral for oral care nor information on the diabetes on gum disease (87; 72.5%). Brushing once daily was practiced by majority of the respondent (107; 89.2%) but most of them (99; 82.5%) do not use any form of interdental cleaning aid [Table 4].

Table 4: Self-perceived problems and knowledge of relationship between diabetes and oral health.

Most of the study participants (108;90%) knew that poor oral health can be injurious to general health and that regular dental cleaning is required even when gum disease is cured (111; 92.5%). Majority of them however had poor knowledge on bleeding associated with gum disease (24; 20%); the formation of calculus below the gum line (25; 20.8%); and the nature of an advanced periodontal disease (17; 14.2%) [Table 5].

Table 5: Knowledge of the respondents about periodontal health.

Table 6 shows the association between the demographic/ clinical characteristics of the respondents and their experience of dental complications related to diabetes mellitus. There was a significant association between the age (p=0.000); educational qualification (p= 0.000); smoking status (p=0.000); duration of diabetes (p=0.000); diabetes type (p=0.000); blood sugar control (p=0.000); and the amount of oral health information received (p=0.000); with the number of dental complications experienced by the participants.

Table 6: Association between demographic/ clinical characteristics of respondents and dental complications.

Table 7 displays the association between dental status and access to oral health information with level of knowledge among the respondents. Participants that had a good oral health status (p=0.000); those that had not lost any permanent teeth (p=0.001); those that had received sufficient oral health information (p=0.000); those that had received a Physicians referral for oral care (p=0.000); and those that had few oral complications (p=0.000); had significantly better oral heath knowledge.

Table 7: Association between dental status and access to oral health information with the level of knowledge among the respondents.

Table 8 displays the logistic regression for dependent variables oral hygiene, dental visits, dental complications and level of knowledge. Frequent tooth brushing was significantly associated with educational status and sufficient information about dental care and oral disease. Participants that had a good oral health status (p=0.000); those that had not lost any permanent teeth (p=0.001); those that had received sufficient oral health information (p=0.000); those that had received a physician’s referral for oral care (p=0.000); and those that had few oral complications (p=0.000) had significantly better oral heath knowledge.

Table 8: Logistic regression for dependent variables oral hygiene, dental visits, dental complications and level of knowledge.

Discussion

Diabetes mellitus is a recognised risk factor for periodontal diseases and diabetic patients tend to have more periodontal destruction than age matched control subjects. [19] Similarly, a higher prevalence of dental caries has been observed in diabetic patients possibly due to alterations in saliva salivary flow rates and high salivary glucose levels. [20] Oral fungal and bacterial infections and oral mucosa lesions such as stomatitis, benign migratory glossitis, fissured tongue, traumatic ulcer, lichen planus, lichenoid reactions and angular chelitis are also more commonly seen in diabetic patients. Optimal control of blood sugar and appropriate oral hygiene measures in addition to regular dental visits has been observed to prevent the oral manifestations of diabetes mellitus. [21,22]

Majority of subjects in this sample were female and there was a preponderance of participants aged 46-65 years. Most of the respondents also had a secondary level of education. The larger representation of females in this sample may reflect the sex related differences in the risk of developing diabetes mellitus and as a result, the differences in the prevalence of the condition across different populations in Sub Saharan Africa. [23] Women also tend to present for their appointments at the diabetic clinic more regularly and tend to have a higher health seeking behaviour than men. Type 2 diabetic patients made up 85.8% of the study population which represents the prevalence in the general population which is close to 90% 1 and this may also reflect a general pattern of attendance as seen in studies with participants that had a similar age distribution. [24]

Most of the respondents rated their glycaemic control as fair or poor and over 90% of participants had a diabetes related complication with numbness in the feet being the most commonly observed complication. This high prevalence of complications may either be related to late presentation before a diagnosis of diabetes was made in the patients or a poor compliance with medication and other management modalities with associated inadequate glycaemic control. Over 11% of the respondents also had a history of current or past cigarette smoking. Cigarette smoking and alcohol consumption have been known to affect the oral microflora adversely. Smoking is also a recognised risk factor in the development of periodontal disease.

A history of past dental visits based on pain and the need for emergency treatment was observed in most of the participants. Only 15% of them reported a dental visit in the year preceding the study while the prevailing reasons for dental visits was toothache and dental emergencies. Over 93% of the respondents also had at least one missing permanent tooth. Xerostomia was observed to be the commonest oral complaint among the study participants. Diabetes induced neuropathy with increased sympathetic stimulation, hypovolaemia resulting from polyuria, and alterations in basement membrane of salivary blood vessels due to AGEs deposition have been implicated in reduced salivary flow in diabetics. It is of utmost significance to educate diabetic patients about the beneficial properties of saliva and its role in the prevention of accumulation of oral biofilm and debris which are primary initiating factors in the development of periodontal disease and dental caries. Diabetic patients should be encouraged to frequently sip small quantities of water, chew xylitol containing chewing gum to stimulate salivary flow or to use artificial saliva substitutes.

It is also noteworthy that even though most of the respondents had one or more dental complaints ranging from burning mouth to painful and sensitive gums, and rated the condition of their mouth and teeth as average or poor, majority of them did not attend the dental clinic and had not received a physician’s referral for dental care. This shows that adequate attention is not given to oral care by diabetic patients and their attending physician. Previous researchers have similarly observed that diabetic patients with poor metabolic control or advanced complications visit the dentist less regularly [25] and are more likely to require emergency dental care than non-diabetic patients. [26] These observations highlight the significance of preventive interventions and oral health promotion for diabetic patients. Health care professionals should make more efforts to implement oral health programs in this group. [27] Oral health problems have a common risk factors with some systemic diseases and health related outcomes. The common risk approach identifies that chronic non-communicable diseases such as obesity, heart disease, stroke, cancer, diabetes, mental illness and oral disease have a set of common risk disorders and factors. [28] This approach can addresses similar aetiological factors or provide interventions that addresses unhealthy lifestyles and habits, thus improving periodontal health and diabetic outcomes.

Most of the participants moreover stated that they had not received sufficient information about oral care while the diabetes nurse was the primary source of oral health information. An assessment of the knowledge of the participants showed that majority of them had poor knowledge on the nature of periodontal disease and its association with diabetes. The findings were in agreement with the observation by Ayanbadejo et al. [29] who also observed a significant relationship between knowledge and educational level of their study subjects. Other researchers similarly observed that diabetic patient did not have adequate knowledge about the oral complications of the disease. [30,31] The amount of health information received by the respondents was also found to be significantly associated with their level of knowledge about oral health.

There was also a significant association between the age, educational qualification, smoking status, duration of diabetes, blood sugar control with the number of dental complications experienced by the participants. Patients below 45 years of age who had Type 1 diabetes and had possibly been diabetic for a longer period were observed to have more complications. There is strong relationship between the oral complications of diabetes and its age of onset. It is imperative that recently diagnosed diabetic patients are appropriately counselled on the association between diabetes and oral health and the need for periodic dental visits to moderate their risk of oral complications.

The American Diabetes Association has stated that all diabetic patients must have a dental referral for a comprehensive oral health assessment as part of the overall management of Diabetes Mellitus. [32] The referral of diabetes patients for dental care is however not yet included in the Clinical Practise Guideline for the management of diabetes patients in Nigeria. This may possibly be one of the contributory reasons for the low referral of diabetes patients for dental care by healthcare workers. It is also imperative that dental professionals are proactive in identifying patients to be screened for diabetes mellitus within the clinic setting and also collaborate with endocrinologist and other physicians to ensure that diabetics have appropriate recall dental visits. [33] Diabetic patients’ self-efficacy and skills should also be improved to perform oral hygiene measures such as tooth brushing and interdental cleaning.

Limitation

The descriptive nature of this study will not permit conclusive inferences to be made from its observations. Another weakness in the method is the use of self-reporting for data collection, which could make some of the responses elicited from the participants subject to recall and “social desirability” bias. Additionally, since the study was conducted in only one centre, the findings may not be generalizable to all Nigerians with diabetes mellitus. The obtained data however provides baseline data for further research in Nigeria.

Conclusion

This study revealed that the oral self-care behaviour of patients with diabetes was not consistent with their increased risk for oral diseases. There was also a low referral of diabetes patients for oral healthcare by medical practitioners. The poor oral health seeking behaviour and low utilization of dental services indicates a need to establish a comprehensive oral health promotion program for the diabetics. Our findings suggest that there is a significant need for increased knowledge of the oral complications of diabetes mellitus and the adoption of preventive oral hygiene behaviours that would improve their oral health.

Conflict of Interest

All authors disclose that there was no conflict of interest.

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